GCALDaemon is a project that offers two-way synchronization between Google Calendar and various iCalalendar compatible apps.

GCALDaemon is an OS-independent Java program that offers two-way synchronization between Google Calendar and various iCalalendar compatible calendar applications. GCALDaemon is primarily designed as a calendar synchronizer but it can also be used as a Gmail notifier, Address Book importer, Gmail terminal and RSS feed converter.